Computer networks typically provide a physical interconnection between different computers to allow convenient exchange of programs and data. A plurality of connectivity devices, such as switches and routers, interconnect each user computer connected to the network. The connectivity devices maintain routing information about the computers and perform routing decisions concerning message traffic passed between the computers via the connectivity devices. Each connectivity device, or router, corresponds to a network routing prefix indicative of the other computers, which it has direct, or indirect access to. Therefore, data routed from one computer to another follows a path through the network defined by the routers between the two computers.
The routers define nodes in a network, and data travels between the nodes in a series of so-called “hops” over the network. Since each router is typically connected to multiple other routers, there may be multiple potential paths between given computers. Typically, the routing information is employed in a routing table in each router, which is used to determine a path to a destination computer or network. The router makes a routing decision, using the routing table, to identify the next “hop,” or next router, to send the data to in order for it to ultimately reach the destination computer.
Networks can include one or more autonomous systems (ASs). An AS is a network or group of networks under a common administration and with common routing policies. Some service providers fear security issues while deploying Inter-Autonomous System (AS) deployment. Although “Inter-AS Option B” Border Gateway Protocol (BGP) Virtual Private Network (VPN) v4 peering between Autonomous System Border Routers (ASBRs) is considered safer than that of the “Inter-AS Option C”, the secured configuration (within BGP) is still highly required to protect the provider infrastructures.